package dao.impl;

import dao.UserDao;
import pojo.User;
import service.UserService;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class UserDaoImpl implements UserDao {


    @Override
    public List<User> findAll() {
        List<User> list = new ArrayList<>();
        //TODO
        Connection connection = null;
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
//jdbc步骤
//1. 加载驱动
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            //2. 创建链接
            String url= "jdbc:mysql://127.0.0.1:3306/jdbc?characterEncoding=utf-8";
            connection = DriverManager.getConnection(url, "root", "227039");
            if(connection != null){
                System.out.println("连接成功");
            }
            //3. 写sql
            String sql ="select * from user";

            //4. 预编译sql
            preparedStatement = connection.prepareStatement(sql);

            //5. 执行sql
            resultSet = preparedStatement.executeQuery();

            //6. 遍历结果
            while(resultSet.next()){
                User user = new User();
                user.setId(resultSet.getInt("id"));
                user.setName(resultSet.getString("name"));
                user.setPass(resultSet.getString("pass"));
                list.add(user);
            }



        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            //7. 关闭资源
            try {
                if(resultSet != null){
                    resultSet.close();
                }
                if(preparedStatement != null){
                    preparedStatement.close();
                }
                if(connection != null){
                    connection.close();
                }

            } catch (SQLException e) {
                throw new RuntimeException(e);
            }


        }

        return List.of();
    }
}
